GeographicTilingScheme

new GeographicTilingScheme

A tiling scheme for geometry referenced to a simple GeographicProjection where longitude and latitude are directly mapped to X and Y. This projection is commonly known as geographic, equirectangular, equidistant cylindrical, or plate carrée.

Parameters:

Name	Type	Argument	Default	Description
`description.ellipsoid`	Ellipsoid	<optional>	Ellipsoid.WGS84	The ellipsoid whose surface is being tiled. Defaults to the WGS84 ellipsoid.
`description.extent`	Extent	<optional>	Extent.MAX_VALUE	The extent, in radians, covered by the tiling scheme.
`description.numberOfLevelZeroTilesX`	Number	<optional>	2	The number of tiles in the X direction at level zero of the tile tree.
`description.numberOfLevelZeroTilesY`	Number	<optional>	1	The number of tiles in the Y direction at level zero of the tile tree.

Source:

/Source/Scene/GeographicTilingScheme.js

Methods

createLevelZeroTiles

Creates the tile or tiles at level of detail zero, the coarsest, least detailed level.

Returns:

Array An array containing the tiles at level of detail zero, starting with the tile in the northwest corner of the globe and followed by the tile (if any) to its east.

extentToNativeExtent

Transforms an extent specified in geodetic radians to the native coordinate system of this tiling scheme.

Parameters:

Name	Type	Argument	Description
`extent`	Extent		The extent to transform.
`result`	Extent	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Throws:

DeveloperError : extent is required.

Returns:

Extent The specified 'result', or a new object containing the native extent if 'result' is undefined.

getEllipsoid

Gets the ellipsoid that is tiled by this tiling scheme.

Returns:

Ellipsoid The ellipsoid.

getExtent

Gets the extent, in radians, covered by this tiling scheme.

Returns:

Extent The extent.

getNumberOfXTilesAtLevel

Gets the total number of tiles in the X direction at a specified level-of-detail.

Parameters:

Name	Type	Description
`level`	Number	The level-of-detail.

Returns:

Number The number of tiles in the X direction at the given level.

getNumberOfYTilesAtLevel

Gets the total number of tiles in the Y direction at a specified level-of-detail.

Parameters:

Name	Type	Description
`level`	Number	The level-of-detail.

Returns:

Number The number of tiles in the Y direction at the given level.

getProjection

Gets the map projection used by this tiling scheme.

Returns:

Projection The map projection.

positionToTileXY

Calculates the tile x, y coordinates of the tile containing a given cartographic position.

Parameters:

Name	Type	Argument	Description
`position`	Cartographic		The position.
`level`	Number		The tile level-of-detail. Zero is the least detailed.
`result`	Cartesian	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Returns:

Cartesian2 The specified 'result', or a new object containing the tile x, y coordinates if 'result' is undefined.

tileXYToExtent

Converts tile x, y coordinates and level to a cartographic extent in radians.

Parameters:

Name	Type	Argument	Description
`x`	Number		The integer x coordinate of the tile.
`y`	Number		The integer y coordinate of the tile.
`level`	Number		The tile level-of-detail. Zero is the least detailed.
`result`	Object	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Returns:

Extent The specified 'result', or a new object containing the extent if 'result' is undefined.

tileXYToNativeExtent

Converts tile x, y coordinates and level to an extent expressed in the native coordinates of the tiling scheme.

Parameters:

Name	Type	Argument	Description
`x`	Number		The integer x coordinate of the tile.
`y`	Number		The integer y coordinate of the tile.
`level`	Number		The tile level-of-detail. Zero is the least detailed.
`result`	Object	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Returns:

Extent The specified 'result', or a new object containing the extent if 'result' is undefined.

<static> WebMercatorTilingScheme#positionToTileXY

Calculates the tile x, y coordinates of the tile containing a given cartographic position.

Parameters:

Name	Type	Argument	Description
`position`	Cartographic		The position.
`level`	Number		The tile level-of-detail. Zero is the least detailed.
`result`	Cartesian	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Returns:

Cartesian2 The specified 'result', or a new object containing the tile x, y coordinates if 'result' is undefined.

<static> WebMercatorTilingScheme#tileXYToExtent

Converts tile x, y coordinates and level to a cartographic extent in radians.

Parameters:

Name	Type	Argument	Description
`x`	Number		The integer x coordinate of the tile.
`y`	Number		The integer y coordinate of the tile.
`level`	Number		The tile level-of-detail. Zero is the least detailed.
`result`	Object	<optional>	The instance to which to copy the result, or undefined if a new instance should be created.

Returns:

Extent The specified 'result', or a new object containing the extent if 'result' is undefined.